1. Field of the Invention
Aspects of the present invention relate to a battery pack and a method for manufacturing the same.
2. Description of the Related Art
Unlike primary batteries which cannot be recharged, secondary batteries can be repeatedly charged and discharged. Low capacity batteries that use single battery cells are used as power sources for various small portable electronic devices such as cellular phones and camcorders. High power batteries that use tens of battery cells connected to each other in a battery pack are used as power sources as motor driving power sources, such as electric scooters and hybrid electric vehicles.
The secondary battery can be fabricated into various shapes, such as cylindrical and prismatic shapes. A high-capacity secondary battery is composed of a plurality of unit secondary batteries which are generally connected in series. Each of the unit batteries includes an electrode assembly having a positive electrode plate and a negative electrode with a separator positioned therebetween, a case enclosing the electrode assembly, a cap assembly coupled to and sealing the case, current collectors of the positive and negative electrodes protruding to the cap assembly and provided in the electrode assembly, and positive and negative electrode terminals electrically connected to the current collectors. Therefore, the battery module includes the plurality of unit batteries spaced at predetermined intervals and connected to each other by electrode tabs in series or in parallel. The battery module is inserted into the spacer, so that the unit batteries are spaced apart from each other.
In addition, the battery module is accommodated within an external case together with an electrically connected protective circuit board, thereby forming a battery pack.
The battery pack is accommodated in the external case and the battery module can move due to external shock, so that the respective unit batteries are disconnected from each other. In addition, the unit batteries and the protective circuit board may also be disconnected from each other.
In this regard, a crack preventing member has conventionally been provided between the battery module and an inner wall of the external case to prevent the battery module from moving within the external case. In the conventional battery pack, however, the number of components may increase, resulting in an increase of the manufacturing cost, and it is quite difficult to fabricate a separate crack preventing member, lowering the manufacturability.